<template>
  <div :style="{ width: '49.5%', display: 'inline-block' }">

    <h6 v-if="total > 0" class="text-center text-muted pt-0 mb-3">
      {{ title }}<br>({{ total }})
    </h6>
    <h6 v-if="total === 0" class="text-center text-muted pt-1 mb-1">
      no data for<br> {{ title }}
    </h6>

  </div>
</template>

<script>
import * as d3 from 'd3'

function InitChart (vueContext) {
  // Female - Male - Other - Unknown

  const pie = d3.pie()
    .value(d => d.count)
    .sort(null)

  const arc = d3.arc()
    .innerRadius(vueContext.radius - (vueContext.radius / 2))
    .outerRadius(vueContext.radius - (vueContext.padding * 2))

  const svg = d3.select(vueContext.$el).insert('svg', ':first-child')
    .attr('width', (vueContext.radius * 2) + vueContext.padding + vueContext.padding)
    .attr('height', (vueContext.radius * 2) + vueContext.padding + vueContext.padding)
    .append('g')
    .attr('transform', `translate(${vueContext.radius + vueContext.padding
    },${vueContext.radius + vueContext.padding})`)

  const path = svg.selectAll('path')
    .data(pie(vueContext.graphData.reverse()))
    .enter().append('path')
    .attr('class', (d, i) => `hoverable ${vueContext.colorclass(vueContext.graphData[i].label)}`)
    .style('stroke', 'white')
    .style('stroke-width', '1')
    .attr('d', arc)

  const tooltip = d3.select('body').append('div')
    .attr('class', 'd3-tooltip tooltip')
    .style('opacity', 0)

  path.on('mouseover', function (event, d) {
    const e = path.nodes()
    const i = e.indexOf(this)
    tooltip.html(`<div class='tooltip-inner'>${
      vueContext.graphData[i].count} ${
      vueContext.percentage(vueContext.graphData[i].count)
    }<br>${
      vueContext.nicelabel(vueContext.graphData[i].label)
    }</div>`)
      .style('left', `${event.pageX}px`)
      .style('top', `${event.pageY - 28}px`)
      .style('opacity', 1)
    d3.select(this).style('opacity', 0.5)
  })

  path.on('mouseout', function () {
    tooltip.style('opacity', 0)
    d3.select(this).style('opacity', 1)
  })
}

export default {
  props: {
    title: String,
    graphData: Array,
    radius: { type: Number, default: 60 },
    padding: { type: Number, default: 1 },
    regions: Array,
  },
  mounted: function () {
    if (this.graphData !== undefined && this.total > 0) {
      InitChart(this) // Only init if we have some info
    }
  },
  computed: {
    total: function () {
      let total = 0
      for (let i = 0; i < this.graphData.length; i += 1) {
        total += this.graphData[i].count
      }
      return total
    },
  },
  methods: {
    colorclass: function (label) {
      if (this.regions === undefined) {
        return `gender-display gender-${label.toLowerCase()}`
      }
      return `region-display region-${label}`
    },
    nicelabel: function (label) {
      if (label === 'Male') {
        return 'Male identifying'
      } else if (label === 'NM') {
        return 'Non-cis male identifying'
      } else if (label === 'Unknown') {
        return 'Unspecified or unrecorded'
      }
      return this.regions[label - 1].name
    },
    percentage: function (quantity) {
      return ` (${Math.round((quantity / this.total) * 100)}%)`
    },
  },
}

</script>
